Re: pickup switch, but with a pedal?
Possible: yes, no 2 ways about it.
Practical: depending on the application, it may be. For example in a home studio on a guitar that will never see a stage. I would definitely never even consider such a setup for live use because of it´s potential to get damaged beyong functionality.
But, similar to the idea of phantom powering EMGs or Blackouts, it poses way to many issues to be viable as a marketable tool, especially potential maintenance troubles.